Objectives: This study examines potential predictors (e.g., attachment style, frequency of therapeutic treatment sessions) of client-rated therapeutic alliance between the social worker and client. The relationship between therapeutic alliance and client's psychological outcomes (hope and posttraumatic stress symptoms [PTS's]) was also assessed. Methods: The study sample included 95 of 193 female clients (average age one fourth 39.35, SD one fourth 8.66) at four methadone clinics in Israel. Results: Clients reported a strong therapeutic alliance with their social workers. Stepwise hierarchical multiple regression analyses revealed that only the frequency of treatment sessions, the avoidance dimension of attachment, and less frequent opiate use were significant predictors of therapeutic alliance. Therapeutic alliance significantly predicted hope but did not predict reduced PTS. Conclusions: Implications for social work practice and future research are discussed. (Contains 5 tables and 1 figure.)